I'll try to do my best explaining my doubts.
Im computer engineer (so i dont have much knowledge in pure electronics). Im trying to build a quadcopter using a raspberry.
By now I've managed to extract the angles data using a MPU6050.
Also calibrate and sent PWM pulses to brushless motors using this library (http://abyz.me.uk/rpi/pigpio/).
The problem with the 4 motors im trying to control. All of them are "A2212/13T 1000KV".
Each of them start moving at different PWM range. By default this library uses a range from 0 to 255. One of the motors starts rotating at 160. Another at 220... etc... So the first one is much more fast at full speed than the others... How can this be possible? Am i doing something wrong?
And the calibration. To calibrate (i have done for all of them), set the pulse to full is easy (255), but the low one is not 0. Its 140 more or less. Dont understand this.
Thanks all! Hope I have explained it more or less correctly!
Or maybe the ESC are different? But I think I bought the same for all of them...
It seems after changing the frequency from the default 800Hz to 500Hz for 2 of the motors and calibrating them again makes them work flawless. Both start spinning at a lower and the same width rate so now I get much more full and synchronized thrust.
The one that started spinning before this 2 motors does not work at 800Hz.
And the 4th one returned beeps that indicate it was correctly calibrated, but did not spin at any width rate. At 500Hz spins but at the beginning too much slow...